COMPUTERS AND COMPUTER SYSTEMSComputing Fundamentals Lesson 1, Part 2

Computer Literacy Basics

Morrison & Wells

IDENTIFYING SYSTEM COMPONENTS

Motherboard—system board mounted inside the computer case A circuit board (thin plate or board that contains

electronic components) Contains integral computer components such as.

. . Central Processing Unit Memory Basic Controllers Expansion ports and expansion slots

IDENTIFYING SYSTEM COMPONENTS

Central Processing Unit (CPU) Also called the microprocessor, is the brains of

the computer Contains millions of switches and pathways that

help your computer make important decisions Two primary sections:

Arithmetic/Logic Unit—performs arithmetic computations and logical operations

Control Unit—the “boss”—coordinates all of the processor’s activities

The computer does not understand human language; therefore, everything must be converted to computer language—binary—1’s and 0’s

PROCESSOR SPEED

Machine cycles are measured in. . . Microseconds (millionths of a second) Nanoseconds (billionths of a second) Picoseconds (trillionths of a second)

The fast the machine cycle, the faster your computer processes data.

MHz (megahertz) and GHz (gigahertz)—indicate the speed of the microprocessor clock—timing device that specifies the speed for executing instructions.

BITS & BYTES

1—electricity is present—”on” 0—electricity is not present—”off” Bit—single 1 or 0 Byte—one character—8 bits Kilobyte—approx. 1000 bytes Megabyte—approx. 1 million bytes Gigabyte—approx. 1 billion bytes Terabyte—approx. 1 trillion bytes ***1 GB of data is equal to 450 digital songs

MEMORY

Found on the motherboard Short-term or long-term RAM—Random Access Memory

Also called main memory and primary memory Short-term, volatile Electricity goes off—your research paper is gone

(unless you have saved it!) Want more speed—buy more RAM

MEMORY

ROM—Read Only Memory Non-volatile, permanent even when the power if

off Found on the motherboard ROM chips—found throughout a computer

system BIOS ROM—stores instructions that tell the

computer what to do when it is turned on Cannot write or store data to a ROM Chip

TYPES OF STORAGE DEVICES

Magnetic technology hard drives, magnetic tape, floppy disks, and zip

disks oxide-coated plastic storage media electromagnetic read/write head stores or

retrieves data in circles called tracks

TYPES OF STORAGE DEVICES

Optical Storage Devices Use laser technology to read and write data on

silver platters CDs

CD-DA—digital audio format CD-R—disc-recordable format. Once written, can’t be

changed CD-ROM—read-only memory format can store large

amounts of data—700 floppy diskettes of data CD-RW—rewritable multiple times

DVDs DVD-ROM—much larger capacity than CD-R DVD-RW—larger capacity than CD-RW Blu-ray—large storage capacity (5 times a DVD) and

enables recording and playback of high-def video

TYPES OF STORAGE DEVICES

Solid-state storage Removal media Nonvolatile Processed electronically so no mechanical parts Miniature mobile storage media USB Flash drive

Also known as key drive, thumb drive, jump drive, USB flash memory, and USB stick

TYPES OF STORAGE DEVICES

Network Drives can be a hard drive or tape drive located on a

computer other than the user’s local system Remote Storage—can be on the same network, a

separate network, or the Internet

CARING FOR STORAGE MEDIA

Keep away from magnetic fields such as those contained in televisions and computer monitors (magnetic media)

Avoid extreme temperatures Remove media and store when not in use Hold optical discs such as DVDs by the edges Never remove when the drive light is on Keep discs in a sturdy case when

transporting